Resilient materials are provided for sealing complementary overlapping edges of aircraft on an aircraft fuselage, such as on lap joints or at other locations. A number of problems may be encountered with lap joint sealants. They must be dimensionally appropriate; they must provide an effective environmental seal; they must be adapted to receive rivets; they must maintain resiliency and avoid creep under load; they must be able to withstand repeated thermal and pressure cycling; and they must be cost effective taking into account labor, manufacturing, installation, and in-service. Typically, prior art sealant materials tend to be a compromise.
Air and watertight seals are sometimes created by the use of cured in-place materials, where two parts are mixed together, then applied very thinly to a sealing surface, and allowed to cure after assembly—wet installed. In some assemblies the use of a thin, precured gel, such as polyurethane gel may be desirable. Applicants have found, however, that there are difficulties in handling very thin gel, in particular a gel with no skeleton and less than about 12 mil thick. It tends to come apart very easily as it is tacky and, being thin and lacking structural integrity (no skeleton) may stick to the release paper upon which it is placed.
Applicant has heretofore used gaskets, gasket tape, and other sealants, as well as a method for making gaskets and other sealants as set forth in the following issued patents that are incorporated herein by reference: U.S. Pat. Nos. 6,530,577; 6,695,320; 7,229,526.
Applicant has found certain problems inherent in the manufacture and use of very thin polyurethane only (no skeleton) gaskets.